My fingers are crossed for you! Lower dose is so much better for overall side effects management.
A few thoughts:
1. Are you supplementing with Curcumin.
Significant research is 'hinting' that Curcumin down regulates genes necessary for leukemia proliferation. Not a cure, but may enable you to take lower dose and it be just as effective. I take 2 grams of C3 Curcumin with bioperine (pepper) per day, but when I was at a much higher PCR level, I took as much as six - eight grams per day. I still take 4 grams from time to time spread throughout the day. Curcumin impact on CML is dose dependent so more is better up to around 10 grams per day. One case where more is better. I would take more myself, but C3 is pricey. Two seems to keep me where I am.
2. Are you taking vitamin D3
Vitamin D (which is made by the body from D3 that is ingested) is vital for immune system health including activation of T-cells which attack cancers. Evidence is emerging that high normal vitamin D levels (> 50ng/ml) activates genes which cause leukemia cell apoptosis. Not a cure, just slows down expansion of leukemia and may actually stop it growing. In combination with your low dose dasatinib, may just be the trick to get you back down again.
Keep in mind that you have plenty of time to experiment (i.e. chronic phase; no blasts) so if you have to increase dose, you can do so incrementally (e.g. 40 mg). But I do hope you regain trend down by considering the above.
(could try fasting too!)